10. None of the students have come to class yet, _______________? A. has one? B. have they? C. have them? D. haven't they? 11. Paper was first to make paper money, playing cards or the world’s oldest book – the Diamond Sutra – in the 2nd century by the Chinese. A. to invent B. inventing C. being invented D. invented 13. Go and invite her out! You need to _________ while the iron is still hot A. hit B. strike C. forge D. hammer 14. I know I shouldn't trust people blindly, but I just couldn't help _______ the beggars money A. be given B. giving C. give D. to give 15. Not only _________ us with the preparation, but he also saw it through till the end A. he helps B. he helped C. that he helped D. did he help